堆积碎石土斜坡浅表入渗的空间分布与变异性研究

发布时间：2018-05-28 07:34

本文选题：滑坡 + 堆积碎石土　；参考：《岩土工程学报》2017年08期

【摘要】：为探究强降雨下堆积体斜坡入渗参数的空间分布与空间变异性,通过筛分试验及双环入渗试验分别对堆积体斜坡试验点不同粒径区间碎石质量分数、碎石土渗透系数、饱和渗透系数、不同深度碎石土含水率进行测量,对数据进行普通Kriging插值统计分析,运用交叉检验选定合理理论模型与参数,获得其空间分布与变异性特征。研究结果表明:测试区碎石土入渗符合Kostiakov模型;不同粒径区间碎石质量分数采用高斯半变异函数理论模型空间插值精度最高,碎石土渗透系数和不同深度碎石土含水率采用球状半变异函数理论模型空间插值精度最高;粒径大于10 mm碎石主要分布于坡顶与坡腰区域且使该区域碎石土渗透系数的空间变异性相对较大,细小碎石(粒径2~10 mm)则聚积在坡脚位置,碎石土渗透系数速率沿坡面由上至下呈逐渐减少的空间分布趋势;浅土层(0~15 cm)坡腰含水率比坡顶、坡脚要高,而深土层(15~25 cm)坡脚含水率比坡顶、坡腰要高,且随深度增加缓慢上升。研究结果可作为碎石土滑坡降雨致滑的理论参考依据。
[Abstract]:In order to investigate the spatial distribution and spatial variability of the infiltration parameters of accumulative slope under heavy rainfall, the mass fraction of crushed stone and the permeability coefficient of gravel soil in different particle size intervals of the test site of the accumulation body slope were studied by sieving test and double-ring infiltration test. The saturated permeability coefficient and moisture content of gravel soil with different depth were measured, and the data were analyzed by Kriging interpolation. The reasonable theoretical model and parameters were selected by cross test, and the spatial distribution and variability characteristics were obtained. The results show that the infiltration of crushed stone in the test area accords with the Kostiakov model, and the spatial interpolation accuracy is the highest by using the Gao Si semi-variogram theory model with different particle size interval. The theoretical model of spherical semi-variogram is used to interpolate the permeability coefficient of gravel soil and the moisture content of gravel soil at different depths with the highest precision. The gravel with diameter larger than 10 mm is mainly distributed in the area of slope top and slope waist, and the spatial variability of the permeability coefficient of gravel soil in this area is relatively large, while the fine gravel (particle diameter of 2mm 10 mm) accumulates at the foot of the slope. The velocity of permeability coefficient of gravel soil decreased gradually from top to bottom along the slope, the water content at the bottom of the slope was higher than that at the top of the slope, and the water content at the foot of the slope was higher than that at the top of the slope, and the water content at the bottom of the slope was higher than that at the bottom of the slope. And it increases slowly with the depth. The results can be used as a theoretical reference for landslide induced by rainfall.
【作者单位】：成都理工大学地质灾害防治与地质环境保护国家重点实验室;湘潭大学土木工程与力学学院;岩土力学与工程安全湖南省重点实验室;
【基金】：国家自然科学基金项目(51108397) 湖南省自然科学基金项目(2015JJ2136) 湖南省教育厅优秀青年项目(16B255)
【分类号】：TU43

【相似文献】